This invention relates generally to medical instruments, and, more specifically, to a navigable catheter device positionable within a body of a patient using an externally applied magnetic field.
Catheters are flexible, tubular devices that are widely used by physicians performing medical procedures to gain access into interior regions of the body. Careful and precise positioning of the catheters within the body is important to successfully completing such medical procedures. This is particularly so when catheters are used to produce emissions of energy within the body during tissue ablation procedures. Conventionally, positioning of such catheters was accomplished with mechanically steerable devices. More recently, magnetically navigable catheter devices have been developed that may be navigated with an externally applied magnetic field. Such catheter devices can be complex in their construction, and therefore are difficult to manufacture and relatively expensive to produce.
Magnetic stereotactic systems have been developed that are particularly advantageous for positioning of catheters, as well as other devices, into areas of the body that were previously inaccessible. Such systems utilize computer controlled superconducting coils to generate specific magnetic fields or gradients to move a catheter that is provided with magnetic components responsive to such magnetic fields. The magnetic fields and gradients are generated to precisely control the position of the catheter within the patient's body. Once correctly positioned, physicians may operate the catheter, for example, to ablate tissue to clear a passage in the body. Specifically, such stereotactic systems monitor the position of a tip of the catheter in response to the applied magnetic fields of the superconducting coils, and using well established feedback and control algorithms the catheter tip may be guided to and positioned in a desired location within the patient's body.
The magnetic response of the catheter can be a limitation on the precise control of a catheter when used with such magnetic guidance systems. Improvements in catheters utilized with magnetic guidance and control systems, such as stereotactic systems, are desired. Specifically, a low cost, yet high performance magnetically guided catheter is desirable.